Adenocarcinoma of the female Praomys (mastomys) natalensis prostate has been induced with intraprostatic 20-methylcholanthrene and transplanted. Testosterone enanthate has been given during induction. Under investigation are acid phosphatase and citric acid production by the tumor. Response to hormone manipulation with estrogen, prolactin, testosterone, cyproterone acetate and ionizing radiation are planned. Content of LDH isozymes is being studied. Various neoplastic and other diseases of mastomys are being recorded. Estrogen-independent renal cell carcinoma of hamsters is being transplanted and harvested. Tumor will be characterized for hyperclacemic and erythropoietic properties and its effect on liver function studied.